象山水库除险加固“两墙”之间砂砾石充填灌浆试验

“两墙”之间的砂砾石过渡层相当于一道厚重的“海绵体”镶嵌在“两墙”中间,是一道柔性支撑体.如果砂砾石的空隙率过大,支撑体的支撑强度就会降低,水库蓄水后会导致防渗体变形过大;如果灌浆后砂砾石的强度过大,超过塑性混凝土墙的强度,砂砾石层就会变成刚性支撑体,对防渗墙适应变形能力有影响,因此进行充填灌浆试验是必要的.     

高液限粉土砾石防渗心墙施工控制参数的确定

结合印尼Jatigede大坝工程现场施工情况,简述了粘土心墙堆石坝高液限粉土砾石心墙施工控制参数的确定过程,提出了高液限粉土砾石防渗心墙的施工控制参数,可为类似工程提供一定的参考。     

黄河海勃湾泄洪闸地基振冲碎石桩现场试验

黄河海勃湾水利枢纽工程位于8度地震区,在地震荷载作用下,泄洪闸地基第Ⅱ-2地质单元沙砾石存在局部液化的可能,因此设计采用振冲碎石桩予以处理。地基振冲碎石桩现场试验结果表明:碎石桩方案能够使沙砾石层相对密度Dr大于0.75,从而消除泄洪闸地基沙砾石的液化问题;桩径为1 m、桩间距为2.2 m的方案能够满足设计要求;将动力触探击数N63.5作为碎石桩桩间土的检测依据是可行的。     

砂卵砾石覆盖层上闸坝防渗体系布置

渗漏与抗渗稳定性问题一直是覆盖层上建设闸坝过程中遇到的一个极其重要的工程地质问题.结合牟汶河拦河枢纽工程,对砂卵砾石覆盖层上闸坝防渗体系布置进行详细介绍,该工程建成后,实际运行状态及监测数据表明采用的防渗措施安全有效.     

THE NATURAL CONVECTION OF AQUIFERS WITH CONSTANT HEAT SOURCES AND ITS INFLUENCE ON TEMPERATURE FIELDS

By combining sand tank tests with numerical simulations, this paper studies the temperature fields around constant heat sources to reveal the mechanism of the natural convection and its influence on the temperature fields in the process of energy storage. Using the "24-channel temperature auto acquisition system" developed by our research group in the tests, the temperatures are recorded at measuring points within the research area in the tests, the revised Brinkman equation and a transfer-convection balance model are used for solving the aquifer water-thermal coupling problems, and through comparison of the test results with the calcula- tion results, it is discovered that the influence ranges and the variations of the two temperature fields are consistent, which validates the mathematical model. On the basis of this, we also study the influences of the heat source positions and the boundary conditions on the temperature fields, and the results show that, under the natural convection, the heat source positions may influence the distri- bution of the temperature fields, thus affect the energy storage. For the same energy storage layer, the temperature field for the top energy storage is characterized by a smaller heat influence range and a relatively concentrated temperature distribution. However, when the heat source is at the bottom, the range of a temperature field, and the temperature is relatively dispersed, which is not favorable to heat recycle, with the same heat source position, the boundary conditions determine the size of the critical Rayleigh number, and thus have an influence on the occurrence and the strength of the natural convection, and accordingly, on the temperature fields.     

截渗技术在龙窝橡胶坝设计中的应用

透水地基存在浸没和渗透变形问题,是渗透破坏险情的易发地段。龙窝橡胶坝为解决坝基渗透问题,在上游地基中设置了一道混凝土防渗墙。为解决绕坝和两岸渗漏问题,在橡胶坝上游左右两岸各约1.45 km范围,采取铺设复合防渗土工膜作防渗处理,同时为防止两岸的渗漏对两岸滩地造成渍害,在两岸滩地采取埋置导渗排水管的措施。     

利用连通试验查找导水通道的应用研究

为探查潘北煤矿井田内主要断层的导水、阻水性,及太原组CI3组灰岩含水层与寒武系含水层之间水力联系,采用连通试验方法,即从寒武系观测孔内注入KI示踪剂,在试验放水巷道放水点进行采样,分析示踪剂浓度随时间变化特征,结果表明:寒武系灰岩水仅与CI 3下存在局部水力联系,与CI1、CI2灰岩含水层间无水力联系,同时也表明寒武系灰岩水通过不同尺度的导水断层,对CI3下含水层发生补给.灰岩露头区的F1、DF1均为导水断层.试验成果为在开采A组煤层过程中对底板灰岩水害防治提供了科学依据.     

偏离度在找水可行性论证中的应用——以包头地区为例

激发极化找水作为一种手段,解译上经验性的成分居多,致使许多专业人员对于能否利用该法找水举棋不定.偏离度参数的提出,大大地提高了对含水性判断的准确性,加之屏障装置测深推断更加接近真深度,使得在包头地区找水的可行性论证有了依据.     

焦作矿区底板含水层注浆改造技术研究与应用

根据焦作矿区地质构造和L8、L2、O2主要灰岩含水层富水特征以及水害威胁严重这一实际情况,详细介绍了焦作矿区煤层底板含水层注浆改造技术的可行性和必要性,重点阐述了煤层底板含水层注浆改造技术的内容及应用效果,总结所取得的经济效益和安全效益.     

连续级配碎砾石粗细颗粒区分粒径分析

粗细颗粒区分粒径是连续级配碎砾石细粒含量判别法判别渗透变形类型重要指标,但目前为止,粗细颗粒区分粒径确定方法和量值均不一致,为验证2个典型方法及量值的适宜性和符合性,统计分析了45个工程179个试样的渗透变形试验结果,结果表明,定值法中以2 mm作为粗细颗粒区分粒径时,其渗透变形类型判断结果与试验结果符合率达80.7%,远高于变值法中以(d_(70)d_(10))~(1/2)为区分粒径时的符合率54.2%。推荐以2 mm作为不均匀连续级配碎砾石粗细颗粒区分粒径。